Improving the long-term stability of bismuth alloy well plug systems

提高铋合金井塞系统的长期稳定性

• 批准号: 453357-2013
• 负责人: Birss, Viola
• 金额: $ 9.47万
• 依托单位: University of Calgary
• 依托单位国家: 加拿大
• 项目类别: Collaborative Research and Development Grants
• 财政年份: 2014
• 资助国家: 加拿大
• 起止时间: 2014-01-01 至 2015-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=555026
• 关键词: Improving; long; term; stability; bismuth

Hydrocarbon resource development is a key driver of the Canadian economy. This has led to the emission of harmful gases, the build-up of carbon dioxide (CO2) in the atmosphere, and the potential for contaminating ground water from wells. Whether lowering pollution, employing hydraulic fracturing, or sequestering CO2 underground, strategic plugging of old and redundant wellbores is critical. Of the roughly 400,000 wells in Alberta in 2012, the number of wells that need to be properly plugged could well exceed 50,000, and this number is growing dramatically. Although Alberta leads the world in tough standards governing the unintended contamination of ground water and release of particularly harmful gases, plugging technologies have not kept pace with the vast number of wells that need to be retired. Seal Well Inc., an Alberta-based company, has patented an alternative wellbore plugging technology based on a bismuth-tin (Bi-Sn) alloy that should be less costly to install, while being far more reliable than current methods. To adapt this technology to the growing use of highly corrosive, pressurized CO2 for enhanced oil recovery and CO2 sequestration, it is necessary to demonstrate that the Bi-Sn alloy and the surrounding steel will have the useful service life needed to form a permanent plug. The focus of this project is to determine the corrosion susceptibility of the Bi-Sn alloy /steel system under realistic down-hole conditions and address corrosion issues encountered from acid gas attack through a combination of strategies. For the first time, a method of applying corrosion inhibitors and oxygen scavenger to Bi-Sn/steel systems will be developed and tested in CO2-saturated brine. Also, the surface structure of the Bi-Sn alloy will be modified to make it more corrosion resistant, and methods of electrolytic cathodic protection and addition of protective Bi coatings onto the Bi-Sn surface, will be explored. The outcome of this work will be the significant extension of the useful service life of the Seal Well technology under harsh underground conditions, thus containing a significantly escalating pollution problem throughout the world, as well as the training of a large number of personnel in corrosion technologies.

碳氢化合物资源开发是加拿大经济的主要驱动力。这导致了有害气体的排放，大气中二氧化碳（CO2）的积累，以及污染水井地下水的可能性。无论是降低污染、采用水力压裂还是在地下封存二氧化碳，对老井和冗余井的战略性封堵都至关重要。2012年，艾伯塔省大约有40万口井，需要适当封堵的井数量可能超过5万口，而且这个数字还在急剧增长。尽管艾伯塔省在管理地下水意外污染和特别有害气体排放方面的严格标准处于世界领先地位，但封堵技术并没有跟上大量需要淘汰的油井的步伐。总部位于阿尔伯塔省的Seal Well公司已经获得了一项基于铋锡（Bi-Sn）合金的替代井眼封堵技术的专利，该技术的安装成本更低，同时比现有方法更可靠。为了使该技术适应越来越多地使用高腐蚀性、加压二氧化碳来提高采收率和二氧化碳封存，有必要证明Bi-Sn合金和周围的钢将具有形成永久堵塞所需的有效使用寿命。该项目的重点是确定实际井下条件下Bi-Sn合金/钢体系的腐蚀敏感性，并通过组合策略解决酸性气体腐蚀问题。将首次开发一种将缓蚀剂和氧气清除剂应用于Bi-Sn/steel体系的方法，并在二氧化碳饱和盐水中进行测试。此外，还将改进铋锡合金的表面结构，使其具有更强的耐腐蚀性，并探索在铋锡表面进行电解阴极保护和添加保护性铋涂层的方法。这项工作的结果将是在恶劣的地下条件下显著延长密封井技术的使用寿命，从而遏制全球范围内显著升级的污染问题，并培训大量腐蚀技术人员。